Carburetor



March 15, 1932. A. SCHOELLER CARBURETOR Filed Sept. 20, 1927 Patented Mar. 15 1932 UNITED STATES PATENT OFFICE.

ALFRED SCHOELLER, OF FRANKFORT-ON-THE- M 'AIN, GERMANY CARBURETOR Application filed September 20, 1927, Serial No. 220,723, and in Germany September 27, 1926.

This invention relates to carburetors in which the fuel-supply is regulated by means of a bafile-plate exposed to the suction-draft of the air.

This invention has for its object to neutralize a number of disturbing influences which make it difficult or impossible to equalize the quantity of outflowing fuel with the fuel-consumption of the motor or with the' quantity of air flowing through the carburetor.

As the air-draft passing through the carburetor is not produced by a source of power acting constantly but by reciprocating pistons which suck in the air in jerks it is unavoidable, even if there are a great number of pistons which are staggered, that also the discharge device, operated by the bafile-plate, vibrates. The vibrations are not prejudicial unless the average stroke of v the fuel-discharge-valve be disturbingly influenced by resonance or interference.

Anyone skilled in the art knows that in connection with fuel discharge-valves which are lifted more or less by bathe-plates, buffersprings and similar devices have to be used which are however arranged so that they distort and displace the oscillating amplitude, but do not make the same harm ess in a sufficient degree.

According to the invention the fuel-discharge valve is loosely arranged between the 4 arm of the baflielate bearing from below ffectivefrom the that the damping-means produces always and the ressureolt of the counter spring of the va ve, bearin from above, merely the pivot-axle of the ba e-plate having a damping-means which acts uniformly towards both sides and produces always only a temporary counter-pressure. From "this arrangement result three oscillating systems, i. ((31. 1) the bathe-plate, (2) the valve-body an of the 'valve, so that formation of resonances and interferences is made difiicult. Speciallyby the arrangement of the damping means .of a baflie-plate' and by a separation of the fbafile'plate from the valve, a. great portion lofj the disturbing movement is made inefeginning. It is important 3) the spring-controlled pressure-bolt only a temporary counter-pressure and has not a shock accumulating effect.

A further impeding of the uniform discharging of the fuel from the dischargevalve is due to the pressure-difierences formed in the carburetor-channel around the baffle-plate. By the suction-draft from the engine a conversion of speed into over-pressure is produced underneath the baffle-plate, and behind the bafile-plate a suction-vortex is produced. This suction-vortex has andfeet upon the fuel-valve which cannot be calculated and, according to the invention, it is rendered ineffective by the arrangement underneath the valve-disk of the fuel-valve of one or several air-channels communicating with the atmosphere. As, however, by all these means an occasional excess of outflowing fuel cannot be avoided so' that there will re- When the front-edge of the cavity is close to the lower edge of the throttle valve the advantage is obtained that the valve moves from the closed position into the open position'very readily and offers in the open position a good discharge path for the air.

An embodiment of the invention is illustrated by way of example, in the accompanying drawings in which Fig. 1 shows the carburetor in longitudinal section.

Fig. 2 shows the battle-plate viewed in the direction of the arrow A Fig. 1.

Fig. 3 is a side-elevation of the carburetor, the damping-arrangement being shown in section. v

Fig. 4 is a top plan view of the carburetor. The carburetor-channel 1 can be opened in the direction towards the sucking piston of the engine to any degree with the aid of the throttle-valve 2. The engine is connected to by the suction-draft and lifts, by means of its arm 4 standing at an angle to said baflieplate, the fuel valve 5. On thefuel-valve 5 rests loosely a bolt 6, controlled by a. valvecounter-spring 7. On the axle 8 of the bafileplate 3 an arm 9 is mounted at an angle outside the channel 1 as shown in Figs. 2 to 4, said arm engaging at the centre of gravity with a piston-body 10., The piston-body 10 is guided in a cylinder 11 which has at the middle apertures 12. The cylinder 10 has in its inner surface narrow flutes permitting the .flowing out of the air which is compressed in the spaces 13. The damper-arrangement 9 to 13 of the bafile-plate opposes consequently a certain resistance at jerk-like displacements, but never a counter-force capable to exert any influence upon the adjusting of the throttle-valve with regard to a constantly cting suction-draft.

- Owing to the arm 4 of the axle 8 of the bafile-plate 3 standing at an angle and resting loosely on the valve-body 5 the oscillating system of the bafile-plate 3 is absolutely separated from the oscillating system of valve 5. As further the bolt 6, controlled by the spring 7, rests loosely from above on the valve 5, this val've 5 is influenced as little as possible by the oscillations of the surrounding elements for providing an open passage. Air-channels 14, communicating with the atmosphere serve to render harmless for the fuel flowing out through valve 5 any suction-vortex which might be produced behind the baflle-plate 3. In the bottom-plate of the carburetor a cavity 15 is arranged, designed to' receive excessive fuel so that this fuel cannot be distributed over too large a surface of the carburetor channel where it would be consumed in a short time and generally forno useful purose. I

On the shaft 19 of the throttle-valve 2 an angle lever 24 is further arranged, the end 25 of which is connected with a push rod 20 hearing against a lever arm 21 on the shaft 8 of the flap valve 3. The other end 18 of the angle lever 24 extends into the range of the cam 17 of a lever system 16 adapted to be operated from the drivers seat. As soon as the throttle-valve 2 has been moved by the lever system 16 into the widest open position, the end 25 of the angle lever 24 pushes the push rod 20 to the right, said push rod lifting by means of the lever arm 26 the axle 4 of the flap valve 3 a short distance opening thereby the fuel valve, so that the quantity of fuel necessary for the starting of the engine can drop intothe cavity 15. The push rod 20 does not impede the flap-valve 3 from suflicient oscillating at the full admission period. 22 is an explosion flap arranged on the flap valve 3 so that it can freely oscillate in the direction towards the air admission and designed to prevent that at back firing from the engine a deformation or destruction of the elements occurs.

I claim e 1. A carburetor comprising in combination a casing having a mixture chamber provided with an air inlet and a mixture outlet, a fuel inlet valve discharging in said mixing chamber, a pivotally mounted flap valve adapted to be operated by suction, an inclined arm fixedly mounted on the pivot of said flap valve and adapted to control the opening of said fuel valve and movable independently thereof, and a dash pot arrangement for said flap valve mounted on the outside of the said casing and completely out of communication with the interior of the casing and being adapted to retard uniformly in either direction the opening of said flap valve.

2. A carburetor as specified in claim 1, in which said inclined arm of the flap valve loosely bears from below against ,said fuel inlet valve, a bolt loosely bearing from above on said fuel inlet valve, and a valve counter spring acting on said bolt.

3. 'A carburetor as specified in claim 1, com prising in. combination with the fuel inlet valve the flap valve and the casing of said fuel inlet valve, a bottom plate of said casing having a cavity under said fuel inlet valve in proximity to the lower edge of said flap valve and adapted to collect excessive fuel and to facilitate the flow of air underneath said flap valve.

4. A carburetor as specified in claim 1, comprising in combination with the flap-valve, a throttle-valve in the entrance of said carburetor, a lever positively connected with said throttle-valve, and means for transmitting the movement of said lever upon said flapvalve to make, when said throttle valve is completely opened, said flap-valve oscillate a suflicient degree for starting the engine, said means having such short useful length that said flap-valve can further oscillate at full admission period.

5. A carburetor as specified in claim 1, in which an explosion flap-valve is freely oscillatable in a direction opposite the direction in which the air flows so that at an explosion the gases from combustion can freely flow to the outer side.

In testimony whereof I aflix my signature.

ALFRED SCHOELLER. 

